It is my understanding from looking at the plugin code that the plugin only gets invoked when the user scrolls to the bottom of a list. The problem I am seeing is with the initial store load. The loading mask no longer appears during the initial store load if the plugin is specified. When I comment out the plugin, the loading mask appears normally.

I understand the loading mask is not displayed while fetching subsequent pages, but it looks odd to have a blank list for 10 seconds with no spinner on initial store load when the view is first displayed.